Garage Door Opener

From SGCommand

The G.D.O (aka Garage Door Opener) is a Tau'ri device that transmits a signal to the S.G.C. computer, identifying the SG unit and opening the iris covering the Earth Stargate.

A G.D.O. and iris code (a sequence of numbers that must be manually entered into the G.D.O.) is assigned to every member of every SG team. The codes can be altered if one of the devices is compromised. If a team is captured or too long overdue, their G.D.O.s are locked out of the system. (SG1: "Children of the Gods")

G.D.O.s have also been given to various allies, such as Bra'tac and the Tok'ra. (SG1: "Family", "Serpent's Song")

The Atlantis Expedition also possesses G.D.O.s, but for individual members instead of teams. (ATL: "Rising", "Home")